CCE measurements on heavily irradiated micro-strip sensors

The paper describes a study of the radiation hardness of micro-strip devices, processed on different silicon substrates, designed to explore the feasibility of a tracker system for the experiments upgrade at the Super-LHC (S-LHC) collider. The radiation tolerance of the devices has been established comparing the Charge Collection Efficiency (CCE) measured on irradiated and not irradiated sensors of the same type. The CCE has been measured with minimum ionizing events and the read-out electronics and data acquisition system are the same designed for the CMS experiment at LHC. The performances of different silicon substrates (MCz, Fz, Epi) and different bulk doping types (p, n) have been investigated. The radiation hardness has been studied up to a fluence of $3.5 \times 10^{15} \ \rm{n}_{eq} \ cm^{-2}$, value expected at a radial distance of about 9cm from the interaction point at S-LHC. Preliminary results of radiation hard candidate material are shown. This work is part of the research activities of INFN SMART and RD50 CERN collaborations.